it illustrates a technology that they had. when they got a tip there might be someone in the boat, the suspect sent up the hopper with thermal imaging equipment and it it showed that there was something in that boat because of the heat that was being generated. so that's the picture of form that you see colored in white and eventually in black where they can make out detail. after doing that, they were able to send in a robot with a long arm that was able to pick up the tarp on top of the boat. of course, that told the tale they knew for sure that that suspect was in there and that's when they sent in the s.w.a.t. team and tried to talk him out. there was an exchange of gunfire and the arrest was made. >> what a conclusion. susan candiotti outside the hospital now where the suspect dzhokhar tsarnaev intubated, sedated and officials waiting, hoping they can talk to him soon. susan, thanks very much. >> the suspect's uncle is speaking out. ruslan tsarni said they were brainwashed. take a listen. >> i caught one of the gentleman